HiOne additional thought which came to mind, and I don't think was already mentioned: If there are legitimate subscribers still, could it be because the notifications are not being allowed to queue, and are instead trying to synchronously SMTP the notification emails?
If "Email package size:" is set to 0 in your ACP Email Settings page, at least for troubleshooting purposes try setting it to 20 or so. This will queue the emails rather than trying to send them synchronously.
I think the fact your reduction of subscribers didn't seem to have any significant effect probably already rules this out. But it still seems like a useful test, since the synchronous processing can cause communication-bound delays right at the point of posting in forums and even private messages.
If increasing the package size does have positive effect, note that if your "Email package size:" was at 0 because you were not getting timely email deliveries / sends, setting up a system cron to perform phpBB cron tasks can help overcome this, if that's an option on your hosting.
Thanks for comment- Ive tried to change these settings - was 20, now 50, tried 0 - No impact.
Statistics: Posted by marksolesbury — Thu Jan 09, 2025 5:53 pm